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Practice Listening: Fill in the Blanks (Type In)
ID: #34862
Medium
Interesting Sound
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Interesting sound. I would have guessed a Wild West performer was with a bullwhip while also vacuuming. But no. That sound is apparently produced by the aurora borealis, the northern lights. Since 2,000 researchers at Finland's Aalto University have been audio, as part of what's called the Auroral Acoustics project. Folk tales have long held that the lights also produce odd sounds, but the claims were hard to prove. And some researchers thought that any noises produced by the particles, that cause the light show would be far too high in the sky to be heard on the ground. But the latest results indicate that at least some sounds are produced very close to the ground. A setup of three ground-based allowed researchers to estimate that the sounds occur perhaps just 70 meters up. The results were just presented at the International Congress on Sound and Vibration in Vilnius, Lithuania. More information about the sounds of the northern lights could lead to a more complete understanding of the .
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